Ok...here is my dilema.

I have attempted TNP several times, failing every time. My last attepmt was going excellent. I dissolved 10g phenol in 23g of H₂SO₄ and heated to 100°C for 1 hour. Then I let the solution (slight golden brown color) cool to 25°C and placed it in a water bath. I added HNO₃ (78g;70%) starting with 5 drops at a time and going to 10-15 drops after adding ~20ml keeping the temp. ~30°C and never going over 35°C. After adding ~35ml I had a thick deep red/brown solution with lots of crystals in it. At this point I could take the solution out of the bath as the temp was no longer rising with the addition of the HNO₃, which was now starting to form a layer of liquid on the top. From this point, I added the NA to the solution which was turning into a deep red/orange less viscous solution with the evolution of a little NO₂, but not enought to come out of the 100ml flask. Once it was all added I let the solution sit for ~30min and then drowned it in 600ml of ice/water.

Nadda, nothing, nil, zip....not a single crystal precipitated.....I now have a nice icey cold red/orange solution. http://theforum.virtualave.net/ubb/smilies/frown.gif

What in hell am I doing wrong...god I hope someone can help me.

[This message has been edited by EventHorizon (edited August 11, 2001).]

[This message has been edited by EventHorizon (edited August 11, 2001).]

OK, Picric Acid is a toxic material and must be handled very carefully. Also picric acid will react with many metals to form impact sensitive metal salts, so it must be kept out of contact with metal. That being said, heres were your going wrong:
1. Slowly stir 4UBW(units by wieght) or 2.2 PBV (parts by volume) of sulfuric acid and 1UBW-or 0.9PBV of phenol into an acid resistant container labelled solution A.
2. Use a double boiler to heat this sulfuric acid/phenol solution to about 100*C(212*F). Keep this temperature until there is no longer an odor of phenol. This will take from 15 to 30 minutes. WARNING: Do not lean over the container and inhale deeply, to check for the smell of phenol. The smell is fairly strong, so you will able to check just by standing near the container and taking a little sniff.
4. Remove the solution from the heat and allow to cool below 30*C(86*F).
5. Gently stir 5UBW-or 2.75PBV of sulfuric acid, into the phenol/acid mixture.
6. IN A NEW CONTAINER LABELLED SOLUTION B: Pour 1UBW of water, then slowly stir 3UBW-or1.6PBV of sulfuric acid and 3UBW of nitric acid into the water.
7. Cool solution B for 30 minutes in an ice water bath.
8. Remove solution B, and place solution A(phenol/acid solution) in the ice bath. Refill bath with new ice water.
9. Very slowly (one drop every 10 seconds) stir solution B(nitric acid/sulfuric acid/water), into solution A(phenol/sulfuric acid). If the temperature starts to approach 40*C(104*F), then stop adding solution B(but continue stirring) and allow solution A to cool to below 30*C(86*F) before continuing.
10. After all of solution B has been added to solution A, continue stirring for 10 minutes.
11. Using a double boiler, very slowly heat the mixture to 80*C(176*F) and hold the mixture at this temperature for at least one full hour. Do not allow the temperature to exceed 90*C(194*F)during this step. As soon as the temperature reaches 80*C(176*F), turn off heat and allow to cool to 70*C(158*F) before turning heat back on.
12. Allow to cool to room temperature.
13. IN A NEW CONTAINER: Pour 14UBW of cold water in it. And stir the solution from step 11 into the water.
14. Filter the picric acid crystals out of the mixture. While crystals are still on the filter, gently pour 6UBW of cold water over them to wash away any remaining acid.
Next step involves drying, hope you already now how to do this.

Ok, thanks.

I guess I'm still puzzled why I had a large crop of crystals that dissapeared with the addition of more NA.

Let us know how you go, yield etc.

I'm going to try the previous method one more time but stop when the addition of HNO3 starts to form a layer on top and no longer increases the temp...then drown it in ice/water and filter. If I fail yet again, I'll try the method you posted.